This relates generally to imaging devices, and more particularly, to imaging devices having pixels with buried channel transfer gates.
Image sensors are commonly used in electronic devices such as cellular telephones, cameras, and computers to capture images. In a typical arrangement, an electronic device is provided with an array of image pixels arranged in pixel rows and pixel columns. The image pixels contain a photodiode (or other type of photodetector) for generating charge in response to light (e.g., by photoelectric conversion). Circuitry is commonly coupled to each pixel column for reading out image signals from the image pixels.
In certain applications, a photodiode may become filled with electrons (charge), and excess generated electrons may “spill” or migrate into a neighboring photodiode. These excess electrons, which may be referred to as blooming current or charge, may result when the image sensor is exposed to bright light. In these scenarios, blooming current can create various undesirable artifacts in a resulting image.
It would therefore be desirable to provide imaging systems with improved antiblooming control.